Sökning: "engine excitation"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden engine excitation.

  1. 1. Prediction of engine component loads using previous measurements

    Författare :Pär Mikaelsson Elmén; Mårten Olsson; Jan-Olov Aidanpää; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; engine; engine block vibration; engine block twist; engine block bending; vibration measurement; vibration estimation; rigid body vibrations; assumed modes; bending modes; torsion modes; system modification; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : Internal combustion engines are used in many applications. The same engine type may have different components mounted to it depending upon its use. These engine mounted components need to be designed against fatigue in order to withstand the engine vibrations. Measured engine vibrations are commonly used as input data for fatigue estimation. LÄS MER

  3. 2. Numerical Investigation of the Aerodynamic Vibration Excitation of High-Pressure Turbine Rotors

    Författare :Markus Jöcker; KTH; []
    Nyckelord :Aeroelasticity; Aerodynamics; Stator-Rotor Interaction; Excitation Mechanism; Unsteady Flow Computation; Forced Response; High Cycle Fatigue; Turbomachinery; Gas-Turbine; High-Pressure Turbine; Turbopump; CFD; Design;

    Sammanfattning : The design parameters axial gap and stator count of highpressure turbine stages are evaluated numerically towards theirinfluence on the unsteady aerodynamic excitation of rotorblades. Of particular interest is if and how unsteadyaerodynamic considerations in the design could reduce the riskofhigh cycle fatigue (HCF) failures of the turbine rotor. LÄS MER

  4. 3. Active Engine Vibration Isolation using Feedback Control

    Författare :Claes Olsson; Ahmed El-Bahrawy; Lennart Ljung; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Broad band active vibration isolation of automobile engine using linear and nonlinear feedback control is considered. The objective is to reduce the forces transmitted to the chassis and body, and, thus, reducing vibrations and structure borne noise inside the vehicle compartment when the engine is subjected to different excitations. LÄS MER

  5. 4. Characterization and Control of Multi-Cylinder Partially Premixed Combustion

    Författare :Magnus Lewander; Förbränningsmotorer; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Efficiency estimation; Closed-loop control; EGR; Diesel engine; Partially Premixed Combustion; Combustion control;

    Sammanfattning : In the last decade diesel combustion has developed in a new direction. Research has been carried out trying to prolong the ignition delay and enhance fuel/air premixing to avoid diffusion combustion as well as lowering the combustion temperature through use of EGR. One of these new combustion concepts is Partially Premixed Combustion (PPC). LÄS MER

  7. 5. Numerical Investigation of Aerodynamic Blade Excitation Mechanisms in Transonic Turbine Stages

    Författare :Björn Laumert; KTH; []
    Nyckelord :Transonic Turbines; CFD; Forced Response; Unsteady Aerodynamics;

    Sammanfattning : With the present drive in turbomachine engine developmenttowards thinner and lighter bladings, closer spaced blade rowsand higher aerodynamic loads per blade row and blade, advanceddesign criteria and accurate prediction methods for vibrationalproblems such as forced response become increasingly importantin order to be able to address and avoid fatigue failures ofthe machine early in the design process. The present worksupports both the search for applicable design criteria and thedevelopment of advanced prediction methods for forced responsein transonic turbine stages. LÄS MER